Solenoid contactor



Aug. 7, 1945. M. G. NELsEN SOLENOID CONTACTOR Filed April 16, 1942 Patented Aug. 7,. 1945 oFF-ICE soLENom ooN'rAc'ron l Marvin G. Nelsen, Skokie, Ill., assignor to Guardian Electric Manufacturing corporation of Illinois Applicationr April 16, 1.942, Serial No. 439,226

s claims.

The present invention relates to electro-mag.-l netic devices, and more particularly to solenoid contactors of the type wherein energization of the solenoid controls the make or break of coop-Y erating contact members connected in an electrical circuit.

Itis well known that in solenoid construction it is highly desirable to employ a ferrous metal plug within' the ,'coil, in a position to serve as a stop for limiting the movement of the plungerof the s'olenoid in one direction, and which also serves to increase the magnetic emciency of the assembly and permits a reduction in the effective length of the plunger so that the moving parts of the assembly may be of reduced weight and. thereby insure easier and smoother operation of the device, while at the same time -reducing vibration incident to operation of the solenoid.

A common practice in solenoid construction consists in utilizing a ferrous metal plug, mount.- ed in iixed relation within the coil of the sole-4 noid. In some instances provision has been made .for adjusting the plug with respect to-the coil for vide an improved 'form of unitary solenoid cone 'Co., Chicago, lll., l

Still another object of this invention is to protactor which is relatively simple in construction, capable of quick and easy assembly, durable in operation and which is capable of economical manufacture.

Other objects and advantages of this invention will be apparent from the following description, taken in connection with the accompanying drawing in which- Figure 1 is a plan elevation ofmy' novel solenoid contactor device, embodying thev present invention, with parts broken away to show details oi' construction. y

Figure 2 is a frontend view of the assembly. vFigure' 3 is a rea/r view of the assembly. In the constructionillustrated in the drawing,

- the solenoid contactor device is a unitary assems varying the stroke or range of movement of the* plunger in one direction by the use or shims or'. washers associated with the anchorage structure of the plug within the coil of the solenoid. The

Aaddition or removal of shims or washers is practiced by the "cut and try" methodl andl which,

while obtaining a `i'air degree of adjustment, does not permit obtaining the nicety of adjustment .that is frequently desired and is necessary in connection with solenoids designed for exact or lpre- .l

determined ranges of movement of the plungers, or where the device is designed to exact specilications for use in connection with a predetermined electrical current. Moreover,such prac-` tice has been found to be time consuming and expensive and does not conveniently lend itself to conveniently make such adjustments of the plug of the solenoids in the ileld." y g One of the obiects of this invention resides in the provision of novel means which is constructed and arranged for ease in assembly and by virtue of which construction it is possible to quickly and v easily obtain a nicety of adjustment of the plug so as to obtain a relatively exact predetermined range of movement of the plunger, or by virtue of bly"and includes a mounting bracket provided.

with a base member I0 adapted to be secured to av 'suit-able mounting and an upright mounting member I I. As may be seen in the drawing, the

- entire assembly. is carried by the mounting bracket and includes a solenoid I2 comprising .a cup-shaped housing I 4, the closed end oi which is rigidly secured to one face of the upright member II, such as by spot welding. Mounted within the housing is an annular coil I5 surrounding a tube I8 which serves as a guide for a recipro.

cably movable plunger indicated at I1. The open end of the housing of thesolenoid is .closed byan end plate or disc I9 as seen in Figure 1 of the drawing, and for convenience in assembling, the outer open end-oi' the housing is interiorly shouldered to'receive the disc I9 and the extreme free-edge of the housing is rolled over against the j disc I! so as to permanently enclose the coil I5.

As maybe seen inthe drawingfthe tube It is arcd at one end, as indicated at Ia to abut against the outer end of the coil and the opposite end of the tubeextends through aligned apertures in the closed end of the cup-shaped housling I 4 and the upright member I I, and is-'iiared which'the plunger may be properly and emciently actuated by energizing of the coil by exact elec--- `trical current characteristics.

A further object resides in the provision of a novel construction of a unitary solenoid conv tactor device wherein the` contact elements are fully enclosed Aat all times.

outwardly as indicated at IIb against the outer surface of themember II, to iirmly anchor the cou m position within the housing u, and to permit movement of the plunger with the guide Mounted in the outer end oi' the tube I3 'oi the 'solenoid is a ferrous metal plug 22, thei'orward end of which is formed with a irusto-conical recess, as indicated at 22a,r corresponding generally to the cooperating, tapered, frustoconical end I'la oisthe plunger I1. The other end ofthe plug is formed with a shank 2-3 which may be of the same sine as the plug proper, so

as to obtain increased power for operating upon the plunger. The outer end of the shank 23 which projects exteriorly of the end wall Il is formed with a slot 2l to accommodate a screwdriver or other suitable implement by virtue of which the plug may be quickly and easily rotated so as to move it toward or away from the adjacent end of the tube II and thereby vary its relationship to the cooperating end of the plunger l1. Mounted on the threaded outer end of the shank 2l is a lock'nut 25 adapted to abut against the outer surface of the housing end disc I9 so as to ilrmly and 'ilxedly lock the plug 22 in a desired position or adjustment.

It is by virtue ofethis construction that it is possible to quickly and easily shift the plug 22 axially withinthe tube It so as to obtain maximum emciency in operation of the assembly. Such an arrangement also permits accommodation for variations in manufacture and assembly o! other elements, which may have a bearing on the eiiective operating range of movement of the phmger. In certain devices of this general charactcr, it is highly desirable to obtain a relatively exact range of movement of the plunger and when such range o! movement must be maintained, it win be apparent that there may be variations in the fabrication of other elements associated with the operation end of the plunger, as well as variations in overall dimensions of the assembly of said other elements. Hence, it v is possible to readily accommodate such variations by providing a nicety of adjustment of the plug 22 with respect to the adjacent end of the plunger I1 in order to obtain the exact speciiied range of movement o! the plunger I1. It will also be apparent that in certain instances where a solenoid is constructed to certain speciilcations for operation by a deiiniteelectrlcal current, it is possible that a variation oi' voltage will impair the eilicient operation oi! the plunger of the solenoid. It is. therefore, possible to overcome this condition by the construction described, in order to obtain a nicety of adjustment of the cooperating plug 22 relatively to the cooperating end of the plunger.

Mounted on the upright member I I of the mounting bracketare a plurality of spaced apart studs 3l which extend horizontally in a direction opposite to the solenoid housing Il. Mounted on said studs in abutting relation to the upright member II, is a panel 32 of insulating material on the outer face of which is mounted-at opposite sides of the axis of the solenoid, a pair of contact members 33, 24, including contact buttons 22a and 34a. The outerA ends of the contact members 22 and 34 are provided with suitable terminals 25 and Il, respectively, adapted to be connected in en electrical circuit to be controlled. Mounted on the outer end of the plunger is a contact bar Il positioned against a ilxed stop or abutment shoulder ll on the plunger. Said bar is of elongated form and is providedjwith a pair o! contact buttons Il and Il Vdisposed in alignment with the cooperating contact buttons 12a and 24a, respectively. Surrounding the plunger I'I ia a coil spring I2, extending through anaperture 22o formed in the insulating panel 32, and abutting at one end against the upright member II and at its opposite' end against the' underside of the contact bar 38. Mounted on the extreme outer end oi the plunger is a coil spring M, adapted to react at one end against the top of the contact bar I8 and at its opposite end against a ilxed collar l5 on the outer end of the plunger. It will be apparent that the coil spring 43 normally serves to oppose movement of the plunger and contact'bar 38 and tends to urge the plunger to its extended position as seen in Figure 1 of the drawing. The construction is such that when the solenoid is energized a yielding pressure is imparted to the contact bar 3l by compression of the coil spring Il and by virtue of which movement the contact bar compresses the coil spring 43 until contact buttons 40 and 4I engage contact buttons 433a and 34a. This arrangement of coil springs, which is well-known, is such that when the solenoid is de-energized, the coil spring Il is iirst relieved of its tension so that the iixed abutment shoulder 39 of the plunger imparts a hammer blow" to the contact bar 38 to initiate its outward movement and eilect immediate separa tion of the respective pairs of contact buttons,

and thus tends to reduce the tendency to arcing.

'I'he two sets oi' contact buttons, as well as the outer ends of the plunger and its spring assembly, are fully enclosed by a cap 4i of insulating material. I'his cap is mounted on the outer ends of the studs 30, and is held with the panel 32 ilrmly against the upright member Il by nuts 30a. As may be seen in the drawing. this cap is -formed witli a recess Il for acommodating the outer ends of the contact bar Il and serving to guide the latter in its movement toward and away from the contact buttons 33a and 34a. 'I'he base of said recess, as indicated at 4l, serves to limit the outward movement oi the -contact bar under pressure of the coil spring 43, and this in turn limits tl'e outward movement of the plunger II. The sides of the cap 4S are notched as indicated at 4S, to permit straddling of the contact members 2 2 and 34.

The novel construction oi' the unitary solenoid contactor above described' lends itself to economical manufacture and assembly. lBy

v virtue of such construction, it is possible to fabricate the device as three main assemblies. namely. the mounting bracket and the solenoid field, the insulating panel carrying the contact buttons, and theplunger with its associated springs and contact bar. thus enabling the parts to be quickly and easily assembled and which assembly is completed by the placement of the cap IB in position on the studs.

Although I have herein shown and described one preferred embodiment of my invention, manifestly it is capable of modification and rearrangement of parts without departing from the spirit and scope thereof. I do not, therefore, wish to be understood as limiting this invention to the precise form herein disclosed, except as it may be so limited in the appended claims.

I claim as my invention:

l. For use with a mounting bracket includ? ing a base member and an u'pright member. a solenoid adapted to be supported onsaid upl right member and comprising a cup-shaped housing having the closed end `thereof rigidly secured to the upright member, an annular coll mountedv within the housing, a tube mounted in said coil and having one end ilared against thel vouter end of the coil and its opposite end exmember and flared against the outer surface of said upright member to fixedly secure the coil in the housing, a ferrous metal plunger reciprocably mounted in one end of said tube and having its outer end projecting through said aligned openings, an end plate secured in the open end of said cup-shaped housing, and a ferrous metal plug xedly connected to said plate and extending into the opposite end of the coil.

2. In a device of the character described, the combination of a mounting bracket including a base member and an upright member, a solenoid supported on the upright member and comprising a cup-shaped housing having the closed end thereof rigidly secured to said upright member, an annular coil mounted within the housing, a plunger reciprocably mounted in the coil and having its outer end projecting through aligned openings in said upright member and said closed end of the housing, a plurality of spaced apart studs projecting horizontally from the upright member at the side opposite said housing, a panel of insulating material mounted on the studs adjacent the upright member, a pair of spaced contact buttons on the outer face of the panel, a contact bar mounted on the outer end of and disposed against a xed abutment on the plunger, said bar including a pair of contact buttons aligned for cooperative engagement with the contact buttons on the panel, a coil spring on the plunger between the contact bar and upright member and serving to yieldingly urge the plunger to extended position together with the contact bar and its contact buttons out of engagement with the contact buttons on the panel, and a cap of insulating material mounted on the outer portion of said studs and enclosing the outer end of the plunger, the contact bar and the contact buttons on the panel.

3. In a device of the character described, the combination of a mounting bracket including a base member and an upright member, a solenoid supported on the upright member and comprising a cup-shaped housing having the closed end thereof rigidly secured to said upright member, an annular coil mounted within the housing, a plunger reciprocably mounted in the coil and having its outer end projecting through aligned openings in said upright member and said closed end of the housing, a plurality of spaced apart studs projecting horizontally from the upright member at the side opposite said housing, a panel of insulating material mounted on the studs adjacent the upright member, a pair of spaced contact buttons on the outer face of the panel, a contact bar mounted on the outer end of and disposed against a xed abutment on the plunger, said bar including a pair of contact buttons aligned for cooperative engagement with the lcontact buttons on the panel, a coil spring on the plunger between the contact bar and upright member and serving to yieldingly urge the plunger to extended position together with the contact bar and its contact buttons out of engagement with the contact buttons on the panel, and a cap of insulating material mounted on the outer portion of said studs and enclosing the outer end of the plunger, the contact bar and the contact buttons on the panel, said cap being formed with guideways for guiding the bar during its reciprocable movement and insuring alignment of its contact buttons with the contact buttons on said panel.

4. In a device of the character described, the combination of a mounting bracket including a base member and an upright member, a solenoid supported on the upright member and comprising a cup-shaped housing having the closed end thereof rigidly secured to said upright member, an annular coil mounted within the housing, aplunger reciprocably mounted in the coil and having its outer end projecting through aligned openings in said upright member and said closed end of the housing, a panel of insulating material mounted on the upright member, a pair of spaced contact buttons on the outer face of the panel, a contact bar mounted on the outer end portion of and disposed with the face adjacent said panel against a fixed abutment on the plunger, said bar including a pair of contact buttons positioned for cooperative engagement with the contact buttons on the panel, a coil spring on the plunger between the contact bar and upright member and serving to yieldingly urge the plunger to extended position with the contact bar and its contact buttons out of engagement with the contact buttons on the panel, a coil spring on the outer end of the plunger engaging the opposite face of said contact bar for yieldingly urging the latter against the xed abutment, and a cap of insulating material mounted on the panel and enclosing the outer end of the plunger, the contact bar and the contact buttons on the panel.

5. In a device of the character described, the combination of a mounting bracket including a base member and an upright member, a solenoid supported on the upright member and comprising a cup-shaped housing having the closed end thereof rigidly secured to said upright member, an annular coil mounted within the housing, a plunger reciprocably mounted in the coil and having its outer end projecting through aligned openings in said upright member and said closed end of the housing, a panel of insulating material mounted on the upright member, a pair of spaced contact buttons on the outer face of the panel, an elongated contact bar loosely mounted on the outer end portion of and disposed with the face adjacent said panel against a fixed abutment on the plunger, said bar including a pair of contact buttons positioned for cooperative engagement with the contact buttons on the panel, a coil spring on the plunger between the contact bar and upright member and serving to yieldinglyurge the plunger to extended position with the contact bar and its contact buttons out of engagement with the contact buttons on the panel, a coil spring on the outer end of the plunger engaging the opposite face of said contact bar for yieldingly urging the latter against the fixed abutment, and a cap of insulating material mounted on the panel and enclosing the outer end of the plunger, the contact bar and the contact buttons on the panel, said cap being formed with guideways for guiding the bar during its reciprocable movement for insuring alignment of its contact buttons with the contact buttons on the panel.

MARVIN G. NELSEN. 

